Old Navy to lululemon size
The short answer
Old Navy M is lululemon L by the two brands' own charts. 6 of 8 Old Navy sizes land on a different label at lululemon.
Both brands publish the body chest each size is cut for, so every row matches a chest, not a letter.
On 1 sizes the charts land two or more sizes from the same label. Brands do not measure the body the same way, so on those rows treat the chart answer and the same label as the two ends of a range.
| Old Navy | Old Navy builds it for | lululemon, by chart | Same label | lululemon builds it for | lululemon also prints |
|---|---|---|---|---|---|
| XS | chest 36 to 37 in, neck 13 to 13.5 in, sleeve 31.5 to 32 in | XS or S | XS | chest 35 to 36 in | not published |
| S | chest 38 to 39 in, neck 14 to 14.5 in, sleeve 32.5 to 33 in | S or M | S | chest 37 to 38 in | not published |
| M | chest 40 to 42 in, neck 15 to 15.5 in, sleeve 33.5 to 34 in | L | M | chest 41 to 42 in | not published |
| L | chest 44 to 46 in, neck 16 to 16.5 in, sleeve 34.5 to 35 in | XL | L | chest 43 to 45 in | not published |
| XL | chest 48 to 50 in, neck 17 to 17.5 in, sleeve 35.5 to 36 in | XXL or 3XL | XL | chest 46 to 48 in | not published |
| XXL | chest 51 to 53 in, neck 18 to 18.5 in, sleeve 36.5 to 37 in | 3XL | XXL | chest 50 to 52 in | not published |
| XXXL | chest 55 to 57 in, neck 19 to 19.5 in, sleeve 37.5 to 38 in | 5XL | 3XL | chest 56 to 58 in | not published |
| XXXXL | chest 58 to 60 in, neck 20.5 to 21 in, sleeve 38.5 to 39 in | 5XL | 4XL | chest 56 to 58 in | not published |
What wearers say
Charts describe a garment, not a fit. We do not collect fit reports for this category yet, so this table is the two brands' own claims and nothing more.
Sources
- Old Navy size guide, read on 2026-09-18. Old Navy on TrueToSize
- lululemon size guide, read on 2026-09-18. lululemon on TrueToSize